Caffeine, alcohol, nicotine, weed, shrooms, acid, speed, coke, mdma, ketamine...
I stopped weed first, nowadays it's just caffeine...
Od'd on speed once, seriously convinced I was dying, that was horrible, 5 days of paranoid hallucinations, I was at my own funeral, people only came to bitch about me...
acid is ok, shrooms are better, mdma and shrooms is amazing.
...but stopped when I became a dad, 17 years ago...